Process of preparing pictures to be produced by tanning action



a instance 7 pigment-printing,

Patented June. 3, J

UNITED; mus PATENT mc mnxmmmn PAUL scnmn'r, nunonr zAim,BADEN-IBIEBRIOH, GERMANY, nssrenoas ro CORPORATION OE GERMANY rnocnss orranrmme rrc'runns To an rnonucnnsx :mmrnve acrron No Drawing Applicationfiled August 7,

aration of pictures to be produced by the action of tanning substances.

In certain photo printingprocesses (for printing, ozotypic printing orthe like) and also in many other arts of printing (copper' deepprinting, photo-lithography, photo-printing, etc.), the la ers preparedwith salts of chromic acid ta e a prominent place in spite of thedisadvantages they show, the .most serious drawback being that,notwithstanding the many attempts made in this respect (see for instanceNamias, Eders Jahrbuch, 1904, page 142), it has not beenpossible tostabilize the colloid layer sensitized with chromates before exposure tolight so as to render them suitable for technical pur oses. 1n

Colloid layers sensitized by means 0 salts of chromic acid are not onlyunfit for being stored for some time, for even in the course of a fewhours the said layers may under unfavorable atmospheric-conditionsundergo so extensive alterations that it is no longer possible to obtaininvariably good results by using them for-the above mentioned purposes.7

Although attempts have been made to substitute for the chromates otherbodies (see Strasser German Patent No. 160,729, issued April 10, 1905)the use of suchother bodies has not been, adopted in practice owing tothe unsatisfactory photographic results they gave. c

We have now found that the decomposition products of diazo compoundswhich are formed during exposure to light are capable, when subjected toreaction with chromates or any other substance, in the presence of acolloid, of'producing a tanning action. By the term tanning action ishere to be understood that action by which the solubil-- ity or theswelling u of colloids is diminished. A similar actlon to that of abichromate can be produced by other oxidation agents for instanceammonium hypobromite, and likewise diazo compounds of great couplingcapacity. In using stable diazo comounds as for instance orthoorpara-hyroxyor amino-diazo compounds it has being ex 1928, Serial No.298,1 26, and m Germany August 22, 1927.

been found that layers sensitizedtherewith are, when not yet exposed'tolight, of abetter stability than layers prepared from chromates.Moreover the new process is applicable to a much greater variety of purposes because sensitized papers prepared according to this process canbe kept in store fit-for immediate use so that the need not be freshlysensitized whenever they are to be employed. The reat number ofavailable diazo compoun s enables one, .by conveniently varym theproces, to modify extensivelythe gradation of the light-sensitivelayers.

The diazo compounds in question may be incorporated into the colloidlayer when it is b mg repared or by subsequentl plache a er in a bathprepared rom a so ution o the respective diazo compound, if reguired,with a stabilizer or. sensitizer adde thereto. 'The said diazo compoundsmay also be applied alone on a suitable base for instance paper, films,metal-foils or the him), then exposed to light under a correspondinoriginal and finally pressed upon a colloi layer moistened with asolution of a chromate.

Diazo compounds may be used with advantage instead of chromates in allreproducing processes where a tanning effect 1s to be producedon colloidla er by chromates reduced by the action of t e light. Among thoseprocesses may be mentioned: Pi mentprinting, copper-deep rinting, photoithography, phototypy, ge atine-printing, gum-v been washed. In certaincases' it is advan AND wmnnnrxamena, or, HALLE & co. AKTIENGESELLSGBAFT,A

tageous to color the layers before and alsov after washing them.-Furthermore a varnis then the layer developed wit warm waterfand, ifdesired, dusted over with a color dust in order to intensify thepicture.

there may be rolled on the layers in question, after osed to light, afatty color, or only The following examples serve to illustrate ourinvention, but are notintended to limit it thereto. v

1. Pigment paper is placed in a bath prepared with a solution, at 18 C.temperature, of 4; parts of hydrofluoborate ofl-diazoldimethylaminobenzene in 100 parts of water and left thereinuntil it is thoroughly moistened; the paper is then pressed upon a wellnitrocellulose with a gelatine layer of a cleaned glass-plate and driedand, afterdrying, it is detached from the latter. The said diazo.compound may be obtained by diazotizing 1-amino-4;-dimethylaminobenzenein the presence of a hydrofluoboric-acid. After drying, the driedpigment paper is exposed to light under a negative, then placed togetherwith a suitable piece of transfer paper in a 2 per cent solution ofpotassium bichromate, until the pigment paper becomes stretched, thepigment paper and transfer paper are then taken from the bath, pressedupon each other and the picture is developed by dissolving therefrom thegelatine which has not been exposed to light in water of about 40 C.temperature in the manner in which pigment-pictures are usually developed.

2. 4: parts of 4-diaz o-3-methyltdimethylanilinsulfate obtained bydiazotizing 4- amino-3-methyl-1-dimethylanilin in a sulfuric solution,are dissolved in 100 parts of water and this solution is spread onwellsized paper having a smooth surface. After drying, the paper sotreated is exposed to light under a diapositive decomposed through adotted screen. The paper after exposure to light is pressed upon pigmentpaper moistened with a 0.25 per cent solution of potassium bichromateand pressed out, such as it is used for copper etchings (so-calledetching paper), the paper is then drawn off after about one minute andpressed immediately upon the copper plate or copper-cylinder intended toreceive the etching. On the copper the picture is developed as usualwith water of a temperature of 40 C. and then, after drying, etched withferric chloride.

Instead of 4-diazo-3-meth l--dimcthylanilinsulfate there may be use thecadmium salt of l-diazol-monoethylnaphthylamine or the diazo compound ofpara-aminodi'phenylamine.

3. So-called Alberts autotypy-paper is placed in a bath prepared from asolution of 4 parts of the diazo compound from1-amino-2-oxy-acetylamino-5-benzenesulfonic acid in 100 parts of water,dried on a glass plate, then exposed. to light under a negativedecomposed through a dotted screen, placed in a bath prepared from a' 2%solution of potassium bichromate and finally thoroughly watered. On thepicture when dry is applied by a roller a photolithographic re-printingcolor giving a uniformly grey tone and then placed in water. When thepaper has become sufliciently moist, the picture can be developed bymeans of a wet small piece of wedding; after drying the developedpicture it is fur ther re-printed by the usual method on a lithographicstone, zinc or aluminium and further treated.

4. A photo-print film, produced from suitable .de ree of hardness, such'as the known Ag a film, is placed in a bath prepared from 4 parts ofthediazo'compound from v1-amino-2-oxy-3-naphthalenecarboxylic acid in100 parts of water and a small quantity of ammonia, then drawn throughacetic acid and by drying it at 2829 C. a' wrinkled grain is producedthereon. Upon the film so prepared a negative is copied, the filmexposed to light and then placed for 2 minutes in a bath prepared from a2% solution of potassium bichromate, whereupon it is thoroughly wateredand dried. The further treatment and printing are operated in the usualmanner.

5. 10 parts of gelatine, 2 parts of colcothar red iron oxide, 2 parts ofsugar and 60 parts of water are made up into an emulsion and there isthen added a solution, acidified with diluted hydrochloric acid, of 0.5parts of a diazo compound obtained by diazotizing 1-aminoA-phenlyaminobenzene in a hydrochloric solution and 1.5 parts ofsodium 1.3.6-naphthalenetrisulfonate in 20 parts of water; the emulsionthus obtained is poured onpaper in the usual manner and the latterdried, exposed to light and further treated as indicated in Example 2. y

In the following claims by the term tanning action is to be understoodthat action by which the solubility and the swelling up of colloids arediminished under the influence of light.

By the term tanning agent are to be understood ammonium hypobromite,etc., and likewise diazo compounds of great coupling capacity,

\Ve claim:

1. The process of "preparing pictures to be produced by tanning actionconsisting in applying a mixture of a diazo compound and an organiccolloid on a base placing the object to be copied on the layer sensitiveto light, exposing it to light, treating it with a tanning agent anddeveloping it with water.

2. The process of preparing pictures to be produced by tanning actionconsisting in applying a mixture of a diazo compound, an organic colloidand a pigment on a base placingthe object to be copied on the layersensitive to light, exposing it to light, treating it with a tanningagent and developing it with water.

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agent and developing it 'with water.-

' posin in applying a mixture '0 4. The process of preparing pictures tobe produced by tanning action consisting and an organic .colloid on abasf' pl'a'cing the object to be copied on the layer sensitive to light,exposing it to light, treating it' with a solution of a chromate anddeveloping it with water.

5. The process of preparing pictures to be produced by tanning actionconsisting in applying a mixture of a. diazo compound, an organiccolloid and a pigment on a base placing the object to be copied on thelayer sensitive to light, exposing it to light, treating it withasolution of a chromate and developing it with water.

6. The process of preparing pictures to be produced by tannin actionconsisting in applying a mixture 0 a diazo compound, an organic colloid,a pigment and asta-' bilizer on a base placing the object to be copiedon the layer sensitive to light, ex-

it to light, treating it with a solutionof .a c romate and developing itwith water.

7. The process of preparing pictures to be produced by tanning actionconsisting in applying a mixture of a diazo compound containin besidesthe diazo group a basic group an an organic colloid on a base placingthe object to be copied on the layer sensitive to light, exposing it tolight, treating it with a tanning agent and eveloping'it with water.

8. The process of preparing pictures to be produced by tanning actionconsisting in applying a mixture of a diazo compound containing besidesthe diazo group a basic group, an organic colloid and a pigment on abase placing the object to be copied on the layer sensitive to light,exposing it to light,

treating it with a tanning agent and developingrit with water.

9. he process of preparing pictures to be produced by tanning actionconsisting in applying a mixture of a diazo compound containing besidesthe diazo group a basic group,-an organic colloid, a pigment and astabilizer on a base, placing the object to be copied on the, layersensitive to light, exposing it to li ht, treating it with a tanningagent and eveloping it with water.

10. The process of preparing pictures to be produced by tanning actionconsisting in applying a mixture of a diazo compound contaimn besidesthe diazo group abasic group an an organic colloid on a base placing t eobject to be copied on the layer sendiazo compound,

a diazo compound pressing it the layer sensitive to light, exposing itto light, treating it with a, solution of a chromate and developing itwith water.

12. The process of preparing pictures to be produced by tanning actionconsisting in applying a mixture of a diazo compound containing besidesthe diazogroup a basic group, an organic colloid, a igment and astabilizer on a base placing t e object to be copied-on the layersensitive to light, exposing it to light, treating it with' a solutionof a chromate and developing it with water.

13. The process of preparing pictures to be produced by tanning actionconsisting in applying a mixture of the diazo compound of the1A-amino-monoethyl-naphthylamine, an organic colloid, a pigment and astabilizer on a base placing the object to be copied on the layersensitive to light, exposing-it to light, treating it with a solution ofa chromate and developing it with water. I

14. The process of preparing pictures to be produced by tanning actionconsisting in applying a diazo compound on a base placing the object tobe copied on the layer sensitive to light, exposing it to light,pressing it on a layer of an organic colloid, having been treated with asolution of a chromate and developing it with water.

15. The process of preparing pictures to be produced by tanning actionconsisting in applying a mixture of a diazo compound and a pigment on abase placing the object to be copied on the layer sensitive to light.exposing it to light, pressing it on a layer of an organic colloid,having been treated with a solution of a chromate and developing it withwater.

16. The process of preparing pictures to be produced by tanning actionconsisting in applying a diazo compound containing besides the diazogroup a basic group on a base placing the object to be copied on thelayer sensitive to light, exposing it to light, on a layer of an organiccolloid,

aving been treated with a solution of a chromate and developing it withwater.

17. The rocess of preparing pictures to be produced by tanningactionconsisting in applying a mixture of a diazo compound containing besidesthe diazo group a basic group and a pigment on a base plac ng'tho objectto be copied. on the layer sensitive to layer of an organic colloid,having been treated with a solution of a chromate and developing it withwater.

18. The process of preparing pictures to be produced by tanning actionconsisting in applying a 'mixture of the diazo compound CERTIFICATE OFCORRECTION.

Patent No. 1, 762,033.

Granted June 3, 1930, to

MAXIMILIAN PAUL SCHMIDT ET AL.

reb certified that the name of assignee in the above numbered patent waszrl dniiduslj written and printed as "Halie & Co. Aktiengesellscicaft,whereas said .name should have been written. and printed as Kalle 8: Go.Aktiengeseilschatt,

. as shown by the records of assignments in this office; and that thesaid Letters Patents should be read with this correction therein thatthe same may conform to the record of the case in the Patent Office.

Signed andsealed this 2nd day of September, A. 1930.

' M. J. Moore, Acting Commissioner of Patents.

